Emperor Palpatine, also known as Darth Sidious, was the last Supreme Chancellor of the Galactic Republic and the self-appointed Emperor of the Galactic Empire, which he established after orchestrating a full-scale galactic conflict known as the Clone Wars to seize dictatorial powers through special emergency measures given to him by the Galactic Senate.
During the Clone Wars, he was the secret de facto leader of the Separatists as the Sith Lord Darth Sidious, as well as the de jure leader of the Republic, allowing him to plan and execute the entire war, thus resulting in his ultimate triumph with the rise of his Empire.
Considered by many to have been the greatest Dark Lord of the Sith in the history of the Sith Order—something he himself also firmly believed—he was the only Sith Lord in a thousand years to achieve the ultimate goal of the Sith: to eradicate the Jedi Order and bring the Galaxy under the rule of the Sith.
But his greatest strength, what made him the appropriate Sith to exact their order's revenge, was not his supreme and deadly skills in the dark side of the Force, but rather the way he could manipulate beings all across the Galaxy—good or evil. Indeed, the shroud of the dark side clouded everything, as Grand Master Yoda had once said.
A diabolical genius, he exacted the revenge of the Sith not only through political machinations and his mastery of the Force, but also with the help of several powerful apprentices—including Anakin Skywalker whom he manipulated into becoming the Sith Lord known as Darth Vader.
Prior to his ascent to Galactic Emperor, Palpatine used a number of assassins, spies and operatives to achieve his objectives as the Sith Lord Darth Sidious. It was his use of Darth Maul, trained specifically to kill Jedi, who proved effective at handling other tasks, that convinced Palpatine of the usefulness of extremely loyal, effective, and secretive agents. Thus he began developing the Emperor's Hands to create a group that were operatives, not apprentices.
During his reign, Palpatine used the Emperor's Hand to kill enemies where his more obvious tools, like Darth Vader would be ineffective, too public, or inappropriate. The exact number of agents is unknown, but among the ranks were Shira Elan Colla Brie, Mara Jade, and Brakiss.
Palpatine was unconcerned about the Rebellion. For the present, it was useful, to accustom his subjects to a state of permanent martial law. He could accept some interference from the Rebels if it helped him in the long run. Without the Force on their side, they could never truly hurt him. But someone else could, as he slowly became aware.
"We have a new enemy. The young Rebel who destroyed the Death Star. I have no doubt this boy is the offspring of Anakin Skywalker." — Palpatine
Hoping to put an end to the Galactic Civil War and solidify his rule once and for all, Palpatine crafted an intricate plan to lure the entirety of the Rebel Alliance into an inescapable death trap. Palpatine allowed Rebel spies to learn of its location while planting disinformation which suggested the Death Star was not yet operational. In reality, the station's prime weapon was complete and fully functional, and an enormous contingent of the Imperial Navy was there to protect it. Sure enough, the Rebels took the bait and planned to attack the station with all of their resources.
Subsequently, Luke Skywalker, who was convinced that his father could be turned back to the light side, allowed himself to be captured and brought to the Death Star. There, Palpatine manipulated Luke into battling his father so that he could inherit his mantle at the Emperor's side. Luke resisted at first, until Vader probed his mind and learned that Leia was Luke's sister. With this knowledge, Vader speculated that he could corrupt her instead, a threat that enraged the young Jedi and drove him to attack Vader with full fury. Although he nearly killed Vader and cut off his mechanical right hand, Luke controlled his anger at the last minute; realizing that he was dangerously close to suffering his father's fate, he discarded his lightsaber and proudly turned to face the Emperor, stating: "You've failed, Your Highness. I am a Jedi, like my father before me."
"Young fool. Only now, at the end, do you understand. Your feeble skills are no match for the power of the dark side. You have paid the price for your lack of vision. Now, young Skywalker, you will die." — Palpatine
Truly, Palpatine's hubris knew no bounds. But here lay his greatest miscalculation: he had taken Vader's subservience for granted. He had forgotten the very factor that had enabled him to convert Anakin Skywalker: his desperate need to keep those he cared for from dying. And he had never anticipated that the sight of Vader's son writhing in unbearable agony, screaming so loudly that it overwhelmed his audio pickups, would be too much for him, that Vader might actually refuse to watch his son die, that, instead of forever waiting on his master's empty promises, he would stop his son from dying, now, through action. Thus Palpatine did not notice that, right next to him, a long-buried Anakin had decided to vindicate his wife's faith in him. And his son's.
But even death was not the end for Palpatine. Unlike his Sith predecessors, Palpatine had never intended to be replaced by an apprentice, expecting his Empire to rule the Galaxy eternally, with only himself as its true leader. At an unknown point in time prior to his death at the Battle of Endor, Palpatine had found a way to cheat death by preserving his spirit after the death of his body, similar to a Force ghost. He arranged for a series of clones of himself to be created for his spirit to possess, in the event that he would perish. His primary supply of clones was kept on Byss, guarded by loyal Dark Jedi.
It was then that the resurrected Emperor struck. Using his dark powers to create a powerful Force Storm, he swept Jedi Master Luke Skywalker to Byss. There, he revealed himself to Luke, and revealed the power of the dark side. Faced with an immortal foe, Skywalker did the unthinkable—in order to defeat the dark side from within, he knelt before Palpatine, and submitted himself as the Emperor's new Sith apprentice, Darth Krayth.
"One day soon Skywalker will wake up and find that he can no longer go back to his friends. He will look in a mirror and he will see his true face, the face of power… the face of the dark side." — Palpatine
Skywalker was too enmeshed in the dark side to successfully rebel against his new master. It was only from his sister, Leia Organa Solo, that he gained the strength that he needed to free himself from the grip of the dark side.
Together, the pair was able to defeat the Emperor temporarily onboard his flagship. Having returned in yet another clone, Palpatine continued his scourge against the New Republic. The Emperor began to succumb to genetic tampering done to his clones by the treacherous Sovereign Protector Carnor Jax. He tried to clone other bodies so that he could resurrect himself, but Jax had succeeded in tainting even the genetic source material.
With his body wasting away rapidly, he went to the Sith world Korriban to consult the ancient Sith Lords. Too late his body died. Railing and cursing against the Skywalker family, Emperor Palpatine's spirit was dragged into the depths of the Force. There he would experience disembodiment in darkness, perpetual madness as if to always live with an open wound, terror without respite.
Darth Sidious, considered by many to be the greatest Dark Lord of the Sith, was finally dead.
